04.11.2016 - After approximately nine months of construction the moment has arrived: Axpo Tegra AG in Domat/Ems can take up operation of its wood chip drying plant. The new plant was officially inaugurated this morning in the presence of invited guests. With the commissioning of the wood chip drying plant, the wood-fired power plant, which produces electricity, process and useful heat, can begin running at full capacity again.
Following hydropower, wood is the second most important renewable energy in Switzerland. Axpo Tegra AG has been operating Switzerland’s largest, CO2-neutral biomass power plant in Domat/Ems for eight years. The eco-friendly wood-fired power plant utilises wood chips stemming from local forest, field and garden waste wood. In order for the wood-fired power plant to achieve the highest possible ecological efficiency, the waste heat has to be used optimally. The plant needs more customers in addition to the neighbouring EMS-CHEMIE AG. From now on, one of those customers will be the new wood chip drying plant.
A great deal of construction went on over the past months: Since January, Axpo Tegra AG expanded the existing wood-fired power plant, which currently includes three power plant units and a container drying system, with a state-of-the-art wood chip drying plant that can dry 160m3 of wood per hour. The new plant also includes an exhaust duct, which due to its dimensions had to be transported in two sections each with a length of 21 metres, an inner diameter of 4 metres each, and each weighing an impressive 24 tons.
The energy content of dried wood chips is 45% higher than that of wet wood chips. Using a dry fuel with a constant moisture level optimises combustion and increases the overall performance of the wood-fired power plant. Axpo Tegra AG invested a total of CHF 11.8 million in the wood chip drying plant, of which CHF 7.3 million alone was invested locally in the Canton of Grisons.
Axpo Tegra AG is already the main customer for energy wood from the local forests, and in doing so makes an important contribution to forest management, forest maintenance and minimising natural disasters. With the inauguration of the wood chip drying plant, the wood-fired power plant in Domat/Ems will increase production operations so that Axpo Tegra AG will once again need large volumes of wood from the Canton of Grisons and neighbouring regions. Some 220,000 tons of wood will be needed per year for energy production. With this energy, the wood-fired power plant can supply electricity to the city of Chur round the clock for half a year.
Forestry management partners produce the wood chips directly in the forest. The new wood chip drying plant then processes the wood chips into a versatile, local product (Secolin), which can also be used by other customers such as small, wood-fired communal heating systems. Thanks to the low moisture content, the dried wood chips are a high-energy fuel that significantly improves the efficiency of wood-fired heating systems. The wood chips are also popular as a durable, decorative covering material for gardens, paths and playgrounds.